


And The Ground Beneath You Iron

by zubeneschamali



Category: Supernatural
Genre: M/M, Season/Series 14 Spoilers
Language: English
Status: Completed
Published: 2019-03-04
Updated: 2019-03-04
Packaged: 2019-11-09 01:20:57
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,422
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17992127
Author URL: https://archiveofourown.org/users/zubeneschamali/pseuds/zubeneschamali
Summary: Set after 14.12. Dean's not going to be able to hold out against Michael much longer, so Sam asks him for one last night together. The circumstances of the request are a bit unusual, but when has Dean ever been able to say no to his brother?





	And The Ground Beneath You Iron

**Author's Note:**

> Thanks to dugindeep for the idea of Sam/Dean in the box, and thanks to her and rozearkana for the encouragement to take it in this direction. Many thanks to non_tiembo_mala for beta reading!
> 
> The title is from Deuteronomy 28:23.

"Sam, I really don't think we're both going to fit."

"C'mon, we've been in tighter places." Sam is right behind him, close enough that Dean can feel the heat coming off his body. His hands skim up Dean's arms as he bends even closer, speaking into Dean's ear. "Remember that closet in River Falls?"

He can hear the note of determination underlying Sam's attempt at seduction, like he's talking himself into it. Ordinarily, that would be enough to make Dean turn around and carefully push Sam away until he could sound like he meant it. But this is…an unusual situation, and it was Sam's idea anyway, and so Dean lets himself lean back until Sam's chest is firm and warm against his back. "The grade school, right?"

"Mmm-hmm." Sam starts with the top button on Dean's flannel shirt, slow and careful like they have all the time in the world. "Waiting for the place to empty out so we could smoke the gym teacher's ghost." 

"That was the only time I ever got a cramp in my leg during sex."

Sam gives a soft snort. "And then when you begged me to massage it for you later, you got lucky a second time."

"I don't _beg_ ," Dean insists as he starts to work on his buttons from the bottom up.

He can hear the smile stretch Sam's mouth wide, and he cranes his neck around to kiss him before he can say anything else stupid. 

Sam responds eagerly, spinning him around so he can go to work on Sam's shirt while Sam finishes his off. It's a rhythm they're both familiar with, years of stripping away layers from each other while heat starts to build within them. Dean can't let himself fall completely into it, but his hands know what they're doing even if his mind has to set aside a corner for—

No. He's not going to think about that right now any more than he has to. It's become second nature over the past few months to do two things at once: concentrate on keeping that door closed and locked no matter how loud the shouting and pounding get, even as he plans hunts for the apoca-refugees or makes dinner or flips through reference books alongside his ever-more-desperate brother. 

Their shirts are off now, all of them, and Sam is already reaching for Dean's belt. Dean wants to let go, wants to lose himself in this one last time, but he _can't_ , and goddamnit, this is why he told Sam they couldn't do this while Michael was in his head. If he gets caught up in things, if he loses control, he could—

"I'm here, Dean," Sam says quietly. He's stopped moving, forehead tilted against Dean's, hands resting on Dean's hips. "You do what you have to do. I'm right here."

He lets out a sigh against Sam's mouth. He wants to tell Sam that if he can't pay full attention, there's no point in doing this. But it's not all about him. And Sam was surprisingly acquiescent three days ago when Dean told him this was it, he couldn't hold back Michael any longer, he had to go in the box. 

If Sam wants to give him something to remember him by, maybe that's for Sam's sake as much as his own.

Dean tilts his head up and gives Sam the kind of long, slow kiss that usually only comes when they're languid and panting in the afterglow. Sam hesitates for only a moment before returning the favor, tongue sweeping past Dean's lips and tangling with his. It gets a twitch from below Dean's belt, and he's relieved. At least his body is still paying attention to Sam.

He goes for Sam's jeans then, slow enough that he can feel each tooth of the zipper unlock. Sam shivers against him before pushing Dean's jeans off of his hips, denim rasping down the length of his legs.

They kick off their jeans and socks, and it's cool enough in the workshop that Dean's skin starts to pebble. He sees that Sam's already straining against his boxer briefs, and he's embarrassed for a moment that he's not doing the same. 

There's only a flicker of hesitation on Sam's face before he reaches for Dean, big hand firmly cupping him, cock and balls all at once, and goddamn, he's always been a sucker for Sam's strong hands. He's getting harder already, and it's part of that same familiar rhythm to reach out and do the same, palm running up and down Sam's dick and pulling out the soft cries that Dean loves to hear. 

Sam backs him up a step, and then two. When Dean feels cold metal against his ass, he goes stiff, and not in a good way. Sam doesn't stop, though, yanking down Dean's underwear and pulling him out. The rasp of his calloused hand brings Little Dean out all the way, and there's the first quiet moan from his own throat as he momentarily forgets what's behind him. 

All too soon, though, Sam is leaning forward and whispering, "Climb in."

Dean's eyes fly open, and he stares for a long moment at the pegboard of tools behind Sam. He built the thing based on measurements, hasn't climbed in once to test it out. And to do it now with Sam right here, to have him see where Dean's going to be spending his eternity—

"Please, Dean." Sam's hands are warm on his ribs and hips, stroking up and down as if to ground him in the present. His mouth lands on Dean's neck, gentle scraping of teeth instantly soothed by the press of his lips.

Dean draws in a deep breath. Then he turns around and clambers up on the work table, levering himself over the edge and into the box before he can change his mind.

The metal is cold on his bare skin, and he holds himself stiffly, trying not to touch the sides. It's a bit more spacious than he thought: his arms can fit at his sides, and neither his head nor his feet are touching the top or bottom. _Good, at least you'll be comfy twenty thousand leagues under_ , he snaps at himself.

Then Sam's broad shoulders block the light as he leans over the box. He studies Dean for a moment, then lifts one long leg into the box and plants his knee next to Dean's. He grabs a few objects from the table in one big hand and drops them in between Dean's legs, then finishes climbing in. 

Kneeling over Dean, chest already sheened with sweat, Sam's gaze is warm and determined and the tiniest bit afraid. Dean's so proud of him, and for a just a moment, he lets it out—all of the things he can't say out loud, there in his eyes if Sam will just look for them.

By the slight tremble of Sam's lips, Dean knows he can see them all.

Then Sam twists sideways, straining to lean over and heft the lid of the box from the table.

"Whoa, hey, what are you doing?"

Sam wrestles the lid halfway into position before replying. The remaining light is slanting across his face, throwing it half into shadow. "Giving you the full experience."

"I thought—" Dean stops. "I mean, I didn't realize you meant…" He trails off, feeling like now is a good time to double-check that door is still tight shut. He can still hold out for a couple more days, and damn if he's going to lose it now.

Sam's waiting for him, that same determination written all over his face. "I told you," he said softly. "I want to give you something to remember me by."

_Like that's gonna be a problem_ , Dean scoffs to himself. The bigger problem is that if he starts freaking out when the lid gets shut, it's going to be even harder for Sam to let him go. Better to know that now so they can prepare. 

So he lifts his chin and says, "Bring on the dark, baby."

Sam's look is more knowing than amused, but he braces the lid on his back and maneuvers until he's lowered it into position. There's a scrape and then a soft thunk when it fits into place. Dean's workmanship is damn good, if he does say so himself. It'll have to be welded together from the outside, of course, but there's no light seeping in through any cracks. Just as it should be.

And with no light, his other senses kick in to higher gear. There's the faster-than-normal pant of Sam's breath, the scent of his sweat that's made something thrum in Dean's brain for as long as he can remember. The slide of his skin against Dean's as he lowers himself over him, and oh yeah, Dean might have a little trouble paying attention to that door after all.

He feels Sam's breath on his face, and he opens his mouth to let him in. The slick slide of their tongues comes faster than it did before, the wet sounds magnified in the darkness. Dean's hands roam up and down Sam's back, curves of muscle guiding his fingers. He knows this body as well as his own, has always known it this well.

He'll never forget it no matter how many years he lives.

Sam's reaching between them, and one of the things he brought with him must have been lube, because there's the familiar _snick_ of the cap opening. Dean's already shifting his legs open, but his ankle bangs against the side of the box. He grunts into Sam's mouth, and then Sam's hand is behind his knee, guiding it up and his legs open.

This, too, is part of their familiar rhythm. Even if he can't see it, Dean can picture the furrow of concentration on Sam's brow as he rubs one long finger around Dean's rim, half to prepare and half to tease. He can certainly feel the long slide of that finger inside of him, and he lifts his hips in response, grabbing the backs of both thighs to make it easier for Sam.

One finger soon becomes two, and Sam's so good at this. He's usually doing it by feel anyway, either with his mouth pressed to Dean's or his gaze avidly focused on Dean's face. Dean's breathing is getting faster, cock hardening in response to Sam's gentle but insistent pressure, and he pants out, "C'mon, Sam. Gimme more."

"Whatever you want," Sam replies, and the pressure of three fingers is too much for only a second before Dean forces himself to relax. The pounding in his head intensifies for a moment, and he silently growls at the locked door with his fading strength. He's going to fail, he knows it, but _not yet_.

Dean comes back to himself with Sam nudging at his entrance. "You ready?" Sam asks, voice tight like he's trying to hold himself back.

"Yeah," Dean replies. He shapes his mouth into a smile, lets the warmth of it come through in his voice. "C'mon, Sammy."

The exhale he hears in response sounds half like a sob, but Sam's leaning over him, one hand braced by Dean's head, the other guiding himself in. Dean's already bent double, shins brushing the heavy lid, but he arches up as best he can, lets the soft punch of a grunt come out as Sam eases his way in.

God, it's always been like this, all the way back to their first time: Sam is just that much bigger and thicker than seems reasonable. Then after a second, he fits like he was made for Dean, filling up the spaces inside of him in more ways than one. Like there's nothing else in the world, no room for anyone but the two of them. 

Dean curls one hand through Sam's hair and cups his jaw with the other. It's how he guides himself up to kiss Sam, neck straining forward as Sam starts to thrust into him. They battle for a moment before Dean gets his tongue into Sam's mouth, keeping up the same rhythm as Sam's thrusts into him. It's familiar, and hot, and oddly comforting, and Dean starts to think that maybe it is a good idea to have this memory to lock away with him here in the dark.

Sam's legs have got to be cramped in the lower half of the box, but he's managing somehow. He's starting to get shorter with his thrusts—not like he's about to come, but he's getting there. Dean's not sure he's going to be able to keep up, at least not on his own, so he lets go of Sam's face to get a hand on himself.

Even in the dark, Sam bats his hand away, fingers curling around Dean's cock in a too-loose slide. "Sam," Dean mutters, squirming in protest. Sam's touch grows even lighter, like he knows he's being a brat, and Dean's about to drive a heel into his ass.

Then Sam's grip tightens, exactly the way Dean likes it, flick of the thumb against the head and everything, and hey, maybe Dean will be able to keep up after all. 

He lets go as much as he can after that, chasing his orgasm while paying attention to Sam at the same time. There's a tiny corner reserved for that locked door, but only a tiny one. Arousal is rising up inside of him, fueled by the scent of Sam's sweat and the slide of his skin against Dean's, the press of the metal against his back with Sam's weight on him, the suddenly deeper grunts that mean Sam's only a few thrusts away. Dean chases harder, suddenly desperate to keep up with his brother.

"Now, Dean," Sam breathes out, like he knows what Dean is thinking, even as his grip tightens with a twist.

Dean comes with a cry, clutching at Sam's shoulders as he rockets through his orgasm. Dimly, he hears Sam's long, low moan in response. It almost like Sam is speaking words as he pulses warm inside of Dean, but if so, they're too quiet for Dean to hear.

Their breathing is in sync, sweat mingling together on their chests along with Dean's come. It's like they really are one being right now, and that's exactly the kind of sappy thought that Dean usually tries to avoid. Good thing Sam can't see him right now, or he'd probably see actual hearts in Dean's eyes. Not the way he wants to go out.

There's a rattling somewhere inside of Dean's head, and his eyes widen. "No," he mutters. "No, not now. Not with—" He grabs for Sam, gets a hold of one bicep. "Sam, you gotta get out of here." 

"I'm right here, Dean." Sam drapes himself over Dean, still inside of him, not quite soft yet. "Just hang on."

"What do you—"

Dean doesn't get to finish, because he's suddenly filled with an all-encompassing flash of light. It's brilliant and blue, welling up inside of him and crowding out everything else. 

"No!" he shouts, hand tightening on Sam's arm, focusing on the feel of muscle there. "No, not—"

Dean throws his head back as something comes _out_ of him, burning and sharp and incandescent. It slams into the sides of the box and hisses when it encounters the symbols burned into the metal. It flares blue-hot in the grooves of those symbols, sparks in their curves and lines. 

It lights up Sam's face, grim and determined and yet with a dawning spark of hope.

There's a howling in Dean's head, louder than the pounding ever was, and he screams right back at it. The light is spilling from his eyes, his mouth, his ears, bouncing off the metal walls of the box and making it shudder. He feels Sam still buried inside of him, and he focuses on that, on that feeling of fullness and completion and rightness, like it's the only thing anchoring him to the world.

The howling trails up into a shriek, and the last of the blue-white light thuds into the metal around them. The symbols are faintly glowing, on the lid and underneath him and all along the sides. It's enough light to see Sam, looking down at him with awe and relief.

Dean glares at him. "What the fuck did you do, Sam?"

"Did it work?"

Dean doesn't need to ask for clarification. The door in his mind is blown wide open—but from the _outside_. Scorch marks line the inside of the room and the walls and floor of the imaginary bar built around it. There's no trace of Michael, anywhere. And it's not like before, when he was returned to himself with a cloud he could still feel hanging over his head that later came around to bite all of them in the ass. He feels…free.

A tiny spark of hope leaps to life in his chest.

What he cautiously says is, "Yeah, far as I can tell."

Nodding to himself, Sam says, "We'll have to get Cas to check for sure. Maybe a blood sigil, too, just to be safe."

"What did you _do_?"

Sam shifts his weight, leaning over Dean on his elbows. "It's some of the oldest magic there is, Dean. Sex magic has been around for as long as the angels have existed, probably longer. Between some old scrolls and one of the Men of Letters' notebooks, we pieced it together."

"We." Dean raises his eyebrows. "Please tell me you didn't bring the Junior Hunter Corps into this."

Sam flushes pink. "No, just Cas."

"Are you kidding me?"

"Dean, he's known for a long time. About us. And I couldn't do this alone."

"You couldn't tell me about it, either."

"In case it didn't work." Sam bites his lip, already reddened from where Dean nipped at it earlier. "I couldn't get your hopes up."

"What happened, anyway?"

"The box did what it was supposed to," Sam replies. "It trapped Michael. Not, like, inside the box, but literally _in_ the box. The symbols you carved to hold him inside the container will also hold him within the metal itself."

"So we can take the lid off and climb out." 

"God, yes." Sam smiles down at him. "It's a good thing you did such a great job making this. If that lid hadn't fit into place so well, I wouldn't have risked it."

"So you just…pushed him out of me and into the box." Dean frowns up at Sam. "You fucked him out of me."

Sam quirks up one corner of his mouth. "Soulmates, Dean. Coming together as two halves of one whole means there's no room for anyone else. That was what the scroll said, and that was what I was counting on."

Dean puzzles that over. "I guess we've never…when one of us was possessed, have we?"

"No, but it's not just that. It was also the holy oil with the lube, and the few words of a spell at just the right time."

"When you came," Dean says.

Sam nods, the earnest expression on his face making him look years younger. "And we couldn't have done it without somewhere to send him. Otherwise he would just talk his way into someone else and go at it again."

"We're still dropping this thing in the bottom of the ocean," Dean says, tapping a knuckle against the metal beneath him. 

"Of course we are," Sam agrees. "But even if he gets out, he can't come back for you again. He's out of you for good."

Dean nods, thinking for a moment. The spark of hope flares a little brighter. "We might have to…you know. Reinforce the spell. I'm thinking three or four times a week oughta do it."

Sam narrows his eyes. "It doesn't need any—" Then the light bulb goes on, and he lightly punches Dean in the shoulder. "There you go, begging for more again."

"I am not begging," Dean says loftily. "Just taking precautions."

"Anything you need," Sam replies. He ducks his head to give Dean a long, slow kiss. 

Dean's legs are starting to cramp, but he reaches for Sam to pull him closer. His recharge time isn't as fast as it used to be, but he's pretty sure he can feel Sam getting hard again, still inside of him. And hey, better safe than sorry, right?


End file.
